This project examines the development of molecular mechanisms regulating liver and muscle metabolism during fetal and early neonatal life. Current studies seek to define: (1) insulin receptors and glucocorticoid receptors in fetal liver and (2) control of protein and nucleotide phosphorylation and dephosphorylation reactions by cyclic AMP and by polyamines. BIBLIOGRAPHIC REFERENCES: Eisen, H.J. and Glinsmann, W.H.: Partial purification of the glucocorticoid receptor from rat liver: a rapid, two-step procedure using DNA-cellulose. Biochem. Biophys. Res. Commun. 70: 367-372, 1976. Nakai, C., and Glinsmann, W.: Effects of polyamines on nucleoside-diphosphate kinase activity. Biochem. Biophys. Res. Commun. 70: 367-376, 1977.